The load-bearing components of jacks are articulated to one another at pivoting joints. Most of these parts are shaped out of structural U section. Other load-bearing components, the head and the foot for instance, are provided with laterally elevated flaps. The load-bearing components are attached by overlapping the lengths of section or tabs in the vicinity of the articulations, providing them with bores, and inserting pivots through the bores. German OS 2 231 526 discloses joints of this nature, with pivots in the form of bolts. The pivots disclosed in European Patent 0 332 565 A1 on the other hand are stamped-out necks.
There is a drawback to this system. The lengths of section and tabs in particular must be very thick, especially at their ends, in the vicinity of the joints, that is, to prevent them from buckling subject to lateral forces to the detriment of overall stability. The extra material adds to the weight.
The object of the present invention is a lighter-weight jack with lengths of section that will not buckle.
The jack in accordance with the present invention is lighter in weight than a conventional jack but can support just as heavy a load while remaining reliably upright. The reinforcing welts along the load-bearing components also augment overall stability.